1. Field of the Invention
The present invention relates to a recording tape cartridge and a drive device thereof for positioning a case accommodating a reel, upon which a recording tape such as a magnetic tape or the like is wound, in the drive device.
2. Description of the Related Art
Recording tapes such as magnetic tapes and the like are used as recording media for saving data (information) of computers and the like, for audio uses, for video uses, and the like. In order to prevent damage to a recording surface of such a recording tape, due to adherence of dust or the like to the recording surface, finger contact and the like, the recording tape is employed in a recording tape cartridge. In this recording cartridge, the recording tape is wound onto a reel and the reel is rotatably accommodated in a case formed of resin.
xe2x80x9cSingle reel cartridgesxe2x80x9d, in which a recording tape wound onto a single reel is accommodated in a case (these are principally used for back-up of information for computers and the like), two-reel cartridges, which are provided with two reels for winding and unwinding (for example, audio cassettes, video cassettes and the like), and the like are known as recording tape cartridges. Whenever information is to be recorded or replayed with one of these recording tape cartridges, the recording tape cartridge is loaded at a drive device (a recording/replaying device).
In a state in which the recording tape cartridge has been loaded into the drive device and the case has been positioned in the drive device, the recording tape is drawn out of the case. This recording tape is guided along a predetermined tape path, and is set at a position close to a recording/replaying head of the drive device. In this state, information is recorded onto the recording tape and/or information that has been recorded on the recording tape is replayed.
As a method for positioning a recording tape cartridge in a drive device, there are methods such as that disclosed in Japanese Patent Application Laid-open (JP-A) No. 11-126398. In such a method, seat portions are provided in reference holes, which are provided at two places in a lower surface of the case. Respective positioning pins of the drive device are inserted, and the recording tape cartridge is positioned in horizontal directions. Further, positioning of the recording tape cartridge in a vertical direction is implemented by the positioning pins abutting against the seat portions.
There are many cases in which the reference holes are dually used as hole portions of bosses for screws, which usually fix an upper case and a lower case which constitute the case. However, in such cases, the positions of the reference holes are constrained by the bosses (or the positions of the bosses are constrained by the reference holes). Further, when the hole portions are formed in the case, formation failures such as short shot due to unsatisfactory filling of resin, coarsening of a design surface due to movement of air bubbles during forming, and the like tend to occur.
Furthermore, when hole portions are formed in a case, portions corresponding to the hole portions are usually provided as inserts fixed to a movable-side mold, which are separate bodies from a movable-side mold body. Consequently, flash may occur at a parting portion between the inserts and the movable-side mold body. There is a risk that stripping off this flash may have an undesirable effect on functioning of the tape.
Correspondingly, there are also cases in which inserts are fixed to a fixed-side mold. In such cases, if flash occurs at a parting portion between the inserts and the fixed-side mold, this flash is at an outer side of the case. Therefore, this will not have any effect on functioning of the tape. However, the outer side of the case is a design surface. Therefore, because parting lines will appear on the design surface, this method is not usually employed.
Accordingly, when hole portions are formed in a case, there is some damage due to the provision of inserts at a movable-side mold or a fixed-side mold. On the other hand, in cases in which inserts are not provided, gas retained at a deeper region of a hole portion cannot escape. As a consequence, short shot of a boss is induced. The deeper the depth of the hole, the more remarkably this tendency is exhibited.
In consideration of the situation described above, an object of the present invention is to provide a recording tape cartridge which can be assuredly positioned in a drive device without hole portions being provided.
A first aspect of the present invention is a recording tape cartridge which is loaded in a drive device therefor and used for at least one of recording and reading out information, the recording tape cartridge including: a case accommodating a rotatable reel on which a recording tape is wound; a first angled surface formed at a front end side in a loading direction of the case, the first angled surface abutting against a first reference portion provided at the drive device for providing a first angled surface position; a second angled surface formed at the front end side in the loading direction of the case, the second angled surface abutting against a second reference portion provided at the drive device for providing a second angled surface position, wherein a position of the case relative to the drive in horizontal directions is determined by the first and second angled surfaces.
According to the aspect of the present invention described above, the first angled surface and the second angled surface are provided at the front end side in the loading direction of the case in which the reel around which the recording tape is wound is rotatably accommodated. At least one of the first and second angled surfaces is preferably formed at a corner portion of the loading direction front end surface.
The first angled surface abuts against the first reference portion formed in the drive device, the second angled surface abuts against the second reference portion formed in the drive device, and thus the case and the first angled surface are positioned in the horizontal directions with respect to the drive device.
Here, the angled surfaces provide the principal function of positioning in X and Y directions. Thus, when the recording tape cartridge is pushed into the drive device, the case can be positioned in the horizontal directions (the X and Y directions) simply by the first and second angled surfaces abutting against the first and second reference portions, respectively. Accordingly, reference holes for positioning of the recording tape cartridge in the horizontal directions are not required.
Consequently, when an upper case and a lower case which constitute the case are fixed by screws, there is no need for bosses for the screws to also serve as reference holes. Thus, positions of the bosses are not limited by positions of the reference holes as in the prior art.
Moreover, because the reference holes need not be provided in the case, case formation defects due to provision of the reference holes, such as short shot, coarsening of a design surface due to movement of air bubbles, and the like, are eliminated.
Further, the first angled surface may be dually used as a drawing-out aperture portion. The aperture portion is usually an indispensable requirement of the case of the recording tape cartridge. Because this aperture portion is combined with the first angled surface, it is not necessary to provide the first angled surface separately, and molding process costs can be reduced correspondingly.
Yet further, the second angled surface may be dually used as a generation (type) identification portion, which distinguishes recording capacity, recording format or the like of the tape cartridge. This generation identification portion is generally an indispensable requirement of a case of a recording tape cartridge. Because the generation identification portion is combined with the second angled surface, it is not necessary to provide the second angled surface separately.
Moreover, in cases in which the case is positioned in a vertical direction with respect to the drive device by an underside surface of the case abutting against a reference pin disposed in the drive device, the underside surface of the case is abraded when the case is loaded or removed from inside the drive device, and may become scratched.
In such cases, if a recessed portion is formed in the underside surface of the case and a reference surface which abuts against the reference pin is provided inside this recessed portion, the recessed portion is not abraded when the case is loaded or removed from inside the drive device. Thus, the reference surface can be protected.
Further, the recording tape cartridge may comprise a recessed portion at a loading direction front end surface, and the recessed portion includes the second angled surface.
A second aspect of the present invention is a drive device to which a recording tape cartridge is loaded and used for at least one of recording information to and reading information from the recording tape cartridge, the recording tape cartridge including a case that has a recess portion, a first angled surface and second angled surface at a front end side in a loading direction of the recording tape cartridge, wherein the second angled surface is formed in the recess portion, the drive device comprising: a first reference portion disposed so as to be able to abut to the first angled surface of the case; a second reference portion disposed so as to be able to abut to the second angled surface, whereby the positioning of the recording tape cartridge relative to the drive device in horizontal directions is determined by respective abutting of the first and second reference portions against the first and second angled surfaces.
The drive device of the above aspect of the invention may further comprise a pin, which engages with the recess portion of the recording tape cartridge when the recording tape cartridge is loaded thereto and abuts against the second angled surface. The pin may have a polygonal pillar shape and a surface that is surface-contactable with the second surface.